Answer:
When light enters from air to water i.e. it is moving from rarer to denser medium, it changes its original path as there is a change of speed of light and deflects itself towards the normal. This is known as the refraction of light and this is why a pencil in a cup of water looks as if it is broken and larger.
Explanation:
Answer:
Let's start by understanding what exactly a scientific question is. A scientific question is a question that may lead to a hypothesis and help us in answering (or figuring out) the reason for some observation. A good scientific question has certain characteristics. It should have some answers (real answers), should be testable.
Here's examples of a few:
Why is that a star?
or
What is that star made of?
Hope this can lead you to the answer you're looking for at least!!
Answer:
a)5.88J
b)-5.88J
c)0.78m
d)0.24m
Explanation:
a) W by the block on spring is given by
W= 
kx² = (530)(0.149)² = 5.88 J
b) Workdone by the spring = - Workdone by the block = -5.88J
c) Taking x = 0 at the contact point we have U top = U bottom
So, mg
= kx² - mgx
And, = ( kx² - mgx
)/(mg) = 
]/(0.645x9.8)
= 0.78m
d) Now, if the initial initial height of block is 3
= 3 x 0.78 = 2.34m
then, kx² - mgx - mg =0
(530)x² - [(0.645)(9.8)x] - [(0.645)(9.8)(2.34) = 0
265x² - 6.321x - 14.8 = 0
a=265
b=-6.321
c=-14.8
By using quadratic eq. formula, we'll have the roots
x= 0.24 or x=-0.225
Considering only positive root:
x= 0.24m (maximum compression of the spring)
